I think it could use more contrast. It all feels very dull right now, and some of the smaller details don't read as a result. As a general rule, the smaller the area taken up by a colour, the more contrast it needs to be easily distinguishable from its neighbours. So, a palette meant to be used with small objects and sprites needs more contrast than one meant for art with large areas of colour.
Your hue-shifting seems to be all over the place, and as a result, the scene doesn't feel unified. Hue-shift your shadow colours towards some ambient hue, and your highlight colours towards some other hue. That will help objects drawn with the palette look like they exist in the same space and are illuminated by the same light sources.
Parts of the characters blend into the floor. The bunny is barely visible. This is less of a palette issue and more of a design problem though - you need to design your scenes and characters in such a way that they stand out from the backgrounds. This is a problem that a palette can't solve by itself, as it's about how/where you use the colours.
